Starter control system



Filed July 14, 1934 To ACCELERATOR PEDA L M Z 6/ 74 z; 76

7 m 7 IM mm! 55 113 .9 113 EVE TORS 4 105 'vgfiwvu- 5, m

107 105 ATTORN EY Patented Jan. 18, 1938 UNITED STATES PATENT OFFICE Anderson,

Ind., assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application July 14,

12 Claims.

This invention relates to a system of control for the starting apparatus of internal combustion engines and particularly to those engines used on automotive vehicles.

The present invention relates to improvements in the type of apparatus shown in the copending application of John B. Dyer, Serial No. 653,983, filed January 28, 1933 for Engine control system. That application discloses a circuit which requires the closing of the ignition switch and the closing of a switch coordinated with the engine throttle actuator in order to establish a relay magnet circuit whereby a starter control relay switch is closed in order to effect the closing of other circuits which will cause an electric starter to operate to crank the engine. The circuit of the battery and the relay magnet and the two switches referred to include a part of the gen erator circuit.

It is one of the objects of the present invention to provide a circuit for the relay magnet which is independent of the generator so that thestarter control system would not be rendered inoperative simply on account of failure of the generator to complete a circuit to the battery at the time the generator is at rest. Such failure might occur due to poor electrical contact between the generator brushes and the commutator. In order to accomplish this object the circuit of the relay comprises a storage battery which is grounded, a switch coordinated with the ignition switch, a switch coordinated with the engine throttle actuator, the relay magnet winding and a switch which connects the circuit to the battery through ground while the generator is not running, said last mentioned switch being inoperative when the generator is connected to the battery by the reverse current or cut-out relay. This third switch of the circuit of the engine starter control relay magnet includes a movable contact actuated by the armature of the reverse current relay,

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing wherein a preferred embodiment of the present invention is clearly shown.

In the drawing:

Fig. l of the drawing is a wiring diagram illustrating the present invention.

Fig. 2 is a detail section of a suction operated switch.

In the drawing, 23 designates a generator grounded at 2i and connected by a wire 22 with 1934, Serial No. 135,102

the current winding 23 of a reverse current relay 24. Winding 23 is connected with the frame 25 of relay 24, which frame supports a leaf spring hinge 26 to which one end of the armature 21 is attached. Armature 21 carries a contact 28 engageable with its stationary contact 29 carried by bracket 30 connected by wire 3i with an ammeter 32 connected by wires 33 and 34 with the battery 35 grounded at 36. This completes ,the generator-to-battery circuit. A voltage coil 31 is connected with the relay frame 25 and is grounded at 38. The frame 25 supports a core 39 which is surrounded by the windings 23 and 31 although these windings are shown in the drawing as separated from the core 39. The relay contacts 28 and 29 are closed to complete the battery charging circuit by the magnetic .action produced by current flowing through the voltage winding 31 after the generator has attained a certain voltage. When the contacts 28 and 29 are closed, current then flows through the winding 23 which then cooperates with winding 31 to hold the armature 21 in position to maintain the contact 28 in engagement with the contact 29. It is therefore apparent that the relay can be adjusted so that its contacts will not be separated due to the action of the spring hinge 26 until after the voltage of the generator has fallen substantially below that voltage required for the closing of the relay contacts 28 and 29. I

The main engine cranking circuit comprises the battery 35, wire 34, switch contact 40, movable contact 4i, switch contact 42, wire 43, starting motor 44 which is grounded at 45, and battery ground connection 36. The starting motor 44 operates the shaft 46 along which slides a sleeve 41 which is splined on the shaft 46 and which is operatively connected through a one way or overrunning clutch 48 with a pinion 49 engageable with the engine fly wheel gear 50.

The sleeve 41 is surrounded by a grooved collar 5| which is slidable along the sleeve 41 but normally is held against a shoulder 52 at the left end of the sleeve 41 by a spring 53 interposed between the collar 5i and the clutch 48. The collar 5! is caused to move toward the right in the drawing by lever 54 pivotally mounted upon a shaft 55 and carrying at its lower end a pin 56 received by the groove of the collar 5|. Movement of the lever 54 counterclockwise will cause the sleeve 41 to be moved toward the right and the pinion 49 to become engaged with the fly wheel gear 50. The pinion 49 is withdrawn from the gear 50 by the operation of a spring 51 which surrounds the shaft and bears at one end against a stationary stop 55 and at the other against a stop 59 carried by the lever 54.

The lever 54 is actuated and the switch 49, 4|, 42 is closed by electromagnetic means which comprises a solenoid core 59 and a solenoid armature 5I which are surrounded by electromag net windings 52 and 53. The solenoid core 59 is provided with a central bore for receiving a horizontally slidable plunger or rod 54 provided with two shoulders I55 and I19 between which an insulatingly mounted movable contact 4I is relatively slidable. A spring I14 urges the con-- tact 4I against the shoulder I55. The rod 54 is normally held in the position shown in the drawing with its shoulder I19 bearing against the magnet core 59 due to the action of a spring I54 bearing at one end against the shoulder I55 and at the other end against a stationary part I55 having a projection I52 telescopically fitting within a recess or central bore I5I in the rod 54. The solenoid armature 59 is connected by a pin 14 with a link 15 which carries a stud 15 received by a slot 11 provided in the upper end of the lever 54.

When sumcient current passes through the windings 52 and 5 3, the armature BI is caused to move toward the left in order to effect counterclockwise movement of the lever 54 and the movement of the pinion 49 into mesh with the engine gear 59. This movement of the solenoid 5| also causes the-rod 54 to move to the left carrying with it, due to the action of the spring I14, the switch contact H which is yieldingly pressed into engagement with the contacts 49 and 42 due to the yielding action of the spring I14. When this occurs, current will flow from the battery to the motor 44 thereby causing rotation of its armature shaft 45 and the pinion 49 driven thereby through the splined sleeve 41 and the overrunning clutch 48, thereby causing the flywheel gear 59 to rotate and the engine to be cranked for starting purposes. Should the engine fail to start and the pinion 49 fail to be withdrawn from the fly wheel gear 59 by the action of the spring 51, it is possible to open the circuit of the starting motor by disconnecting the magnet coil windings 62 and 53 from the storage battery, the connections to which are to be described later. 'When the magnet coils 52 and 63 are deenergized, movement of the contact 4I away from the contacts 49 and 42 by the action of spring I54 may take place due to the fact that the solenoid 5| may move toward the right slightly although the lever 54 may not be turned. This is possible due to the lost motion connection provided by the pin 15 and the slot 11 between the solenoid armature 5i and the lever 54.

Should the end faces of the teeth of the pinion 49 abut with the end faces of the gear 59 be fore meshing, it is possible to close the motor circuit in order that the pinion 49 may be rotated into meshing relation with the engine gear 59. This is possible due to the fact that the motor switch 49, 4|, 42 can be closed before the meshing of pinion 49 with gear 59 takes place. The solenoid armature 5| moves to close the motor switch and to move the pinion 49 toward the gear 59; but, after the pinion 49 collides with the gear 59, the spring 53 is compressed beyond its initial state of compression. Then when the motor shaft 45 turns to relieve the condition of gear tooth abutment, the spring 53 is released quickly to snap or jump the pinion 43 into engagement with the engine gear 59.

The circuit for connecting the magnet windings 52 and 53 with the storage battery 35 com-' prises the following circuit: Battery 35, wire 24, contact 49, frame II of the starter control relay 59, leaf spring hinge 52, armature 93, contact 94,

stationary contact 85,bracket 35, wire 31, winding current will flow through both windings 52 and 53 to cause the solenoid 5| to move toward the left in order to shift the pinion 49 into engagement with the gear 59 and to close the motor switch 49, H, 42. When the motor switch closes, the winding 52 will be short circuited. The winding 52 is made preferably of relatively coarse wire whereas the winding 53 is constructed of relatively fine wire. Both windings 52 and '53 are required to draw the armature 5| across to the core 59 but, when this relation has been established, the one winding 53 is all that is required to maintain this relationship. Therefore, the winding 52, which consumes the greater amount of current is short circuited so that the starting motor will have adequate current for cranking the engine.

The circuit of the engine starter control relay 89 comprises battery 35, wire 34, wire 33, ammeter 32, wire ,9I, stationary contact 92 of ignition switch 93, movable contact 94, stationary contact95, wire 95, switch 91, wire 95, relay magnet coil 99 surrounding core I99, wire I9I, bracket I92, contact I93 cooperating with movable contact I94 insulatingly carried by armature 21 of cut-out relay 24, wire I95, and ground returns 35, 35 to battery 35. When the movable switch contact 94 of ignition switch 93 engages contacts 92 and 95 it also engages a contact I95 connected by a wire I91 with the ignition apparatus of the engine. The switch 91 is one which is closed manually and is open automatically when the engine starts. The switch 91 is preferably actuated by the engine throttle actuator or accelerator pedal. It is opened automatically preferably by means responsive to engine intake suction. The switch contacts I93, I94 of the cutout relay 24 are normally closed.

To start the engine, the operator turns on the ignition switch 93 to cause the contact 94 to engage contacts 92, 95 and I95. The operator closes the switch 91 preferably by means coordinated with the accelerator. This causes current to flow from the battery through the coil 99 of the starter control relay 59 whereupon contacts 84 and 55 are closed, whereupon the magnet coils 62 and 53 are energized to effect the shifting of the starter pinion 49 into mesh with the engine fly wheel gear and then closing of the main motor switch 49, H, 42. The engine therefore starts in the manner described. When the engine becomes self-operative, suction produced by the engine will open the switch 91; and, in response to the voltage of the generator 29 driven by the engine, the switch I93, I94 will be open. Hence the circuit of the coil 99 of the starter control relay 00 is opened by two switches connected in series to insure the discontinuance of the engine starting function as soon as possible after the engine becomes selfoperatlve and the prevention of the operation of the starter thereafter or until the engine has stopped.

The construction of the magnet may be varied within certain limits, but it is desirable that the coil 03 shall contain a smaller number of turns than the coil 62, and the resistance of the coil 03 should be higher than the coil 62 so that the flow of current through the coil 63 is as low as possible .to insure that the armature of the magnet be held in switch closing position during the cranking operation, so as to change that position as little as possible. It has been found desirable to provide coils having such resistances that for a six volt battery system, the flow of current through coil 63 is substantially from 8 to 10 amperes and through the coil 62 from 40 to 50 amperes before the starter switch is closed.

The flow of current through the coil 62 is very brief, as it takes an almost imperceptible time to effect closing of the starting motor switch so that during most of the starting operation there is only from 8 to 10 amperes flowing through the coil 63 to hold the starting motor switch closed and the pinion in gearengaging position.

It has been found that in order to cause proper opening of the main starter switch 40, H, 42 upon opening of the ignition switch or the switch 91, the number of turns in the inner, or pull in" coil 62 of the starter magnet must be somewhat greater than the number of turns in the outer, or hold in coil 63. This is true because when either switch above referred to, is opened while the starter switch is closed, current will fiow from the battery through the starter and thence through the coils of the starter magnet to ground, the direction of current in the inner coil being the reverse of that in the outer coil.

As a concrete example of the operation it may be assumed that the switch 91 is opened by suction and the starter switch should open immediately. On opening of switch 91, however, current will flow from the battery to ground through connection 36 and from the battery through wire 34, the starter switch 40, H, 42, wire 00a through the coil 62, thence through wire 90, wire 81, the coil 63 to ground 88, the direction of flow through coil 62 being reversed while the direction of flow through coil 63 remains the same. At this time the coils tend to neutralize each other and in order to insure that the magnetic fiux passes through the zero point immediately, a slightly larger number of turns are used in the inner coil 62. The outer coil 63 may comprise 122 turns of #16 B. E. copper wire, and the inner coil 12'? turns of #11 B. E. copper wire. With this arrangement, as the flux passes through the zero point upon reversal of polarity of the inner coil 62 on opening of the suction operated switch 91, the magnet becomes completely deenergized and the starter switch is opened by the spring I64, as the spring 51 retracts the armature 6| and demeshes the pin ion 40.

Theoretically, it might be possible to eifect opening of the starter switch 40, 4|, 42, with coils having the same number of turns, but owing to the residual magnetism of the magnet, inequalities in the wire resulting in varying resistances, and manufacturing inaccuracies, it is impossible to use coils of the same number of turns as the magnetic flux might not reach zero value. To make sure that the flux pressure does always pass through the zero point, it is necessary to provide at least a few more turns in the inner coil than the outer.

An improved form of accelerator-closed, engine-suction-opened switch 81 is disclosed In the copending application of John B. Dyer, Serial No. 643,375, filed November 19, 1932.

The suction operated switch 91 is shown in detail in Fig. 2 and comprises a diaphragm housing composed of two sheet metal shells I00 and IOI, which are secured together at their periphery to form a fluid-tight joint and between which a diaphragm I02 is clamped. Secured to the V shell IOI of the diaphragm chamber is a cupshaped shell I03 which is closed by a disc of insulating material I04 in which are secured additional contacts I05. Extending through the insulating material I04 and journalled therein for rotation lsa stud I06 to which is secured by riveting or in any other convenient way, a lever arm I01 adapted to be connected to the accelerator pedal for operation therewith. The stud I06 carries a sleeve I00 which is provided with slots I09 diametrically opposed from each other and received in these slots is a movable contact IIO which is rotated with the sleeve when the arm I01 is operated by the accelerator pedal. This contact is carried by a sleeve III which fits within the aforementioned sleeve I08 and is carried by the diaphragm I02, previously referred to. The diaphragm is normally held in the position shown in the drawing by a spring II I which pushes the diaphragm downwardly and tends to force the movable contacts toward the insulating member. A torsion spring 2, one end of which is connected to one of the two pins II3, which are secured in the housing I03, and the other end of which is connected to the movable contact, normally holds the contact in such position that when it is forced downwardly by the spring III, as previously described, it will not engage with the two fixed contacts I05.

The sleeve I00 is provided with shoulders on which the movable contact is adapted to rest during the operation of the engine.

The closing of the switch is effected by movement of the arm I0'I which rotates the movable contacts into engagement with the two fixed con- I tacts. When this takes place and the other control switches in the circuit are closed, the engine starts to run and when the suction becomes effective when the engine begins to run under its own power, the diaphragm is pulled upwardly lifting the movable contact out of engagement with the two fixed contacts and the torsion spring previously referred to then rotates the movable contact in the reverse direction so that it will rest upon the previously described shoulders if the suction falls due to any increase in load or from any other cause in order to prevent any possible closing of the switch during operation of the engine when such decrease in suction takes place. This switch is the one which is illustrated in the previous application Serial No. 643,375 and which is Shown in greater detail therein.

An improved form of magnetic starter switch and starter switch relay unit is disclosed in the copending application of John B. Dyer, Serial No. 653,983, filed January 28, 1933.

The claims of this application are directed to the system of control, particularly to the starter switch relay circuit independent of the generator. The advantage of this circuit over one which includes the generator is readily apparent since it is known that a generator having a gummy commutator might make very poor electrical contact with its brushes while at rest, although, after its commutator had rotated a few revolutions, the generator might be thereafter operative to charge the battery. Any such possibility is avoided by the present invention, since the ground return to the battery of the starter switch relay magnet circuit is provided not by way of the generator and its ground return, but by way of a separate normally grounded switch the contacts of which are separated by the action of the cut-out relay to connect the generator with the battery for charging purposes. Thus the starter control circuit is prevented from function not only by the enginesuction responsive switch 91 but by a switch responsive to generator operation. By making additional use of the cutout relay, this additional preventative switch is provided at but small additional expense. Furthermore, the cutout relay is well adapted for such additional use since it has the characteristic of holding its armature in attracted position until the generator speed has dropped to a very low value.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. In an engine starter control system, the combination which comprises, a storage battery, an engine driven generator for charging the battery, a cut out relay associated therewith, an electric starting motor for starting the engine, and a control circuit operated by said battery for connecting said battery with said electric starting motor, said control circuit including a relay magnet winding, a switch operated by the cut out relay for connecting said relay magnet with the battery independently of both the generator and thestarting motor, and including a second switch operated in response to engine operation.

2. In an engine starter control system, the combination which comprises, a storage battery, an engine driven generator for charging the battery, a cut out relay associated therewith, an electric starting motor for starting the engine, and a control circuit operated by said battery for connecting said battery with said electric starting motor, said control circuit including a relay magnet winding, a switch operated by the cut out relay for connecting said relay magnet with the battery independently of both the generator and the starting motor, including a manually closed switch and a normally closed switch opened in response to suction produced by the engine.

3. In an engine starter control system, the combination which comprises, a storage battery, an engine driven generator for charging the battery, a cut out relay associated therewith, an electric starting motor for starting the engine, and a control circuit operated by said battery for connecting said battery with said electric starting motor, said control circuit including a relay magnet winding, a switch operated by the cut out relay for connecting said relay magnet with the battery independently of both the generator and the starting motor, said means including a manually closed switch and the switch operated by the cut out relay, said last named switch being normally closed and opened in response to the voltage of the generator, and a switch operated by engine suction.

4. In an engine starter control system, the combination which comprises, a storage battery, an engine driven generator for charging the battery, a cut out relay associated therewith, an electric starting motor for starting the engine, and a control circuit operated by said battery for connecting said battery with said electric starting motor, said control circuit including a relay magnet winding and means for connecting said relay magnet with the battery independently of both the generator and the starting motor, and including, in series, a manually closed switch, a normally closed switch opened in response to suetion produced by the engine, and a normally closed switch operated by the cut out relay and adapted to be opened in response to generator operation.

5. In an engine starter control system, the combination which comprises, a storage battery, an engine driven generator for charging the battery, a cut-out relay for connecting the generator with the battery, an electric starting motor for starting the engine, and a control circuit operated by said battery for connecting said battery with said electric starting motor, said control circuit including a relay magnet winding and means for connecting said relay magnet with the battery independently of both the generator and the starting motor and including a normally closed switch opened in response to the operation of the cut-out relay to connect the generator with the battery, and a second normally closed switch adapted to be opened by engine suction.

6. In an engine starter control system, the combination which comprises, a storage battery, an engine driven generator for charging the battery, a cut-out relay for connecting the generator with the battery and including a magnet and armature operated thereby, an electric starting motor for starting the engine, and a control circuit operated by said battery for connecting said battery with said electric starting motor, said control circuit including a relay magnet winding and means for connecting said relay magnet with the battery independently of both the generator and the starting motor, and including a normally closed switch having a movable contact insulatingly supported by the armature of the cut-out relay and opened in response to the operation of the cut-out relay to connect the generator with the battery, and a second control switch adapted to be opened by engine suction.

'7. In an engine starter control system, the combination comprising, a storage battery, an engine driven generator for charging the battery, a cut out relay for connecting the generator with the battery, a starting motor adapted to receive current from said storage battery, a starter switch for controlling the operation of said starting motor, an electromagnet having a winding for operating said starter switch, a magnetic switch in circuit with the winding of said magnet and controlling the operation of said magnet, a control circuit for the magnetic switch for connecting the magnetic switch with the battery independently of both the generator and the starting motor including two engine operated switches, one of which is operated by said out out relay.

8. In an engine starter control system, the combination comprising, a storage battery, an

engine driven generator for charging the battery, a cut out relay for connecting the generator with the battery, a starting motor adapted to receive current from said storage battery, a starter switch for controlling the operation of said starting motor, an electromagnet having a winding for operating said starter switch, a magnetic switch in circuit with the winding of said magnet and controlling the operation of said magnet, a control circuit for the magnetic switch for connecting the magnetic switch with the battery independently of both the generator and the starting motor including a switch operated by engine suction and a second switch operated by said out out relay.

9. In an engine starter control system, the combination comprising, a storage battery, an engine driven generator for charging the battery, a cut out relay for connecting the generator with the battery, a starting motor adapted to receive current from said storage battery, a starter switch for controlling the operation of said starting motor, an electromagnet having a winding for operating said starter switch, a magnetic switch in circuit with the winding of said magnet and controlling the operation of said magnet, a control circuit for the magnetic switch for connecting the magnetic switch with the battery independently of both the generator and the starting motor including a switch operated by engine suction, a second switch operated by said out out relay, and a manually operated switch.

10. In an engine starter control system, the combination comprising, a storage battery, an engine driven generator for charging the battery, a cut out relay for connecting the generator with the battery, a starting motor adapted to receive current from said storage battery, a starter switch for controlling the operation of said starting motor, an electromagnet having a winding for operating said starter switch, a magnetic switch in circuit with the winding of said magnet and controlling the operation of said magnet, a control circuit, for the magnetic switch for connecting the magnetic switch with the battery independently of both the generator and the starting motor including two engine operated switches, one of which is normally closed and adapted to be opened by said out out relay when the engine is running.

11. In an engine starter control system, the combination comprising, a storage battery, an engine driven generator for charging the battery, a cut out relay for connecting the generator with the battery, a starting motor adapted to receive current from said storage battery, a starter switch for controlling the operation of said starting motor, an electromagnet having a winding for operating said starter switch, a magnetic switch in circuit with the winding of said magnet and controlling the operation or said magnet, a

control circuit for the magnetic switch for connecting the magnetic switch with the battery independently of both the generator and the starting motor including a normally open switch manually movable to closed position and movable by the engine to open position and a second switch normally closed and adapted to be opened by the cut out relay when the engine runs under its own power.

12. In an engine starter control system, the combination which comprises, a storage battery, an engine driven generator for charging the battery, a cut out relay associated therewith, an

electric starting motor for starting the engine, and a control circuit for connecting the battery with said starting motor, said control circuit including a relay magnet having a winding, a switch operated by the cut-out relay, a connection extending from said winding to said lastnamed switch and from said switch directly to the battery whereby when said last-named switch is closed said winding is connected directly with the battery, and a second switch for controlling the action of the relay magnet winding.

JOHN B. DYER. WILLIAM E. BROWN. 

